My MGUS was discovered in 2012. To date my M protein has remained low, but my light chain ratio and kappa free quant chains have slowly increased. I am slightly below the threshold for needing a bone marrow biopsy. My problems with fatigue, general malaise, frequent sore throats, chills, etc. began about the same time and have gotten much worse over the years. I 've had to reduce my hours at work to half time and I only go out when I have to. Very frustrating! My physician has not associated my symptoms with the MGUS. She diagnosed me with Myalgic Encephalopathy instead. But, after reading your question and the responses, I may bring it up to her.